JPH10184352A - Outboard motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an outboard motor in which the rise of temperature can be suppressed in a cowling even after the stop of an engine, the generation of bubbles or vapor can be prevented in a fuel supply line, the start failure of the engine can be eliminated and thermal adverse effects to an auxiliary machine or an electrical equipment or the like can be eliminated. SOLUTION: In an outboard motor 1 having a four-cycle engine 8 as a driving source housed in a cowling 5, a part of the cowing 5 is composed of an opening/ closing type duct 20 which is opened/closed (manually or) automatically. Thus, when the opening/closing type duct 20 is opened at least upon stop of the engine 8, the hot air of the cowling 5 is exhausted outside through the opening/closing type duct 20. Accordingly, even after the stop of the engine 8, the rise of temperature in the cowling 5 is suppressed, the generation of bubbles or vapor can be prevented, the start failure of the engine 8 is cancelled and thermal adverse effects to an auxiliary machine or an electrical equipment or the like can be also eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outboard motor in which a four-stroke engine with a built-in oil pan is housed in a cowling.

[0002]

2. Description of the Related Art Since an outboard motor is used on the surface of the water, the engine is generally covered with a cowling to protect the engine from water, and the cowling has a minimum necessary ventilation opening. . For this reason, ventilation in the cowling relies on intake air to the engine. During operation of the engine, the air in the cowling is warmed by heat radiation from the engine, and the temperature in the cowling tends to rise.
In particular, unlike a two-cycle engine, a four-stroke engine does not allow fresh air to flow through the crankcase and circulates lubricating oil, so the temperature of the lubricating oil rises and the amount of heat released from around the crankcase Increase.

[0003] When the temperature inside the cowling rises during the operation of the engine as described above, the density of the air taken into the engine decreases, the filling efficiency decreases, and the engine output decreases, resulting in a decrease in the engine output. In addition to lowering the cruising performance (speed and acceleration) of the engine, air bubbles and vapors are generated in the fuel supply line, causing engine idling and poor starting. In addition, auxiliary equipment and electrical components are adversely affected by heat. Problems arise.

Therefore, a part of the fuel supply line is exposed to the outside of the cowling to cool it (see Japanese Utility Model Laid-Open No. 3-77060), or a fan is provided above the engine to force hot air in the cowling to the outside of the cowling. It has been proposed to discharge (see JP-A-8-100647).

[0005]

However, even in the above proposal, when the engine is stopped, the cooling water is discharged from the engine and the fan is stopped, so that ventilation in the cowling is also stopped. In this case, the heat capacity of the oil pan that stores the lubricating oil increases, and the temperature of the engine itself increases due to the heat radiation from the lubricating oil, and the temperature inside the cowling increases, thus causing the above problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to suppress a rise in temperature in a cowling even after an engine is stopped, thereby preventing generation of bubbles and vapor in a fuel supply line. An object of the present invention is to provide an outboard motor that can eliminate poor starting of an engine and can also eliminate adverse thermal effects on accessories, electric components, and the like.

[0007]

In order to achieve the above object, according to the present invention, there is provided an outboard motor in which a four-stroke engine with a built-in oil pan is housed in a cowling. It is characterized by comprising an openable / closable duct that opens and closes manually or automatically.

According to a second aspect of the present invention, in accordance with the first aspect of the present invention, an actuator which is operated by a battery power supply to open and close the openable duct, and a predetermined time elapses after the engine is stopped by controlling the operation of the actuator. A control means for opening the openable duct is provided until the temperature in the cowling exceeds a set value until the temperature rises.

According to a third aspect of the present invention, there is provided an outboard motor including a four-cycle engine having a built-in oil pan in a cowling, wherein a fan driven by an electric motor operated by a battery power source is provided in the cowling. An exhaust port for discharging hot air inside the cowling to the outside of the cowling is formed in the cowling, and control means for controlling the operation of the electric motor is provided.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the control means controls the fan until the predetermined time elapses after the engine stops or while the temperature in the cowling exceeds a set value. The operation of the electric motor is controlled to drive the motor.

According to a fifth aspect of the present invention, in the third or fourth aspect, an intake port for introducing outside air into the cowling and the exhaust port are separated by a partition.

According to a sixth aspect of the present invention, in the third, fourth or fifth aspect of the present invention, an opening portion into the cowling of the intake duct for introducing outside air into the cowling and the exhaust port are viewed from the side. It is characterized by being arranged on the diagonal of the cowling.

According to the first or second aspect of the present invention, if the openable duct is opened at least when the engine is stopped, the hot air in the cowling is discharged out of the cowling through the openable duct. In this case, the rise in temperature inside the cowling is also suppressed, preventing the generation of bubbles and vapor in the fuel supply line, eliminating poor engine starting and eliminating the adverse thermal effects on auxiliary equipment and electrical components. You.

According to the third or fourth aspect of the present invention, at least when the engine is stopped, the fan is driven by the electric motor operated by the battery power supply, whereby the hot air in the cowling is discharged from the exhaust port to the outside of the cowling by the fan. Therefore, even after the engine is stopped, the rise in temperature inside the cowling is suppressed, preventing the generation of air bubbles and vapor in the fuel supply line, eliminating poor engine startup and eliminating heat to auxiliary equipment and electrical components. Adverse effects are also eliminated.

According to the fifth aspect of the present invention, since the intake port and the exhaust port opened to the cowling are separated by the partition, the hot air in the cowling discharged from the exhaust port during the operation of the engine is discharged from the intake port to the engine. As a result, the engine is maintained at a high filling efficiency and its performance is prevented from deteriorating.

According to the present invention, the opening of the intake duct for introducing outside air into the cowling into the cowling and the exhaust port are arranged on the diagonal of the cowling in a side view. A fan driven after the engine stops generates a flow of outside air in the cowling along a diagonal line in a side view, and the flow of the outside air effectively cools the engine, and the hot air in the cowling is discharged from the exhaust port to the outside of the cowling. .

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

[First invention] An embodiment of the first invention will be described below with reference to the accompanying drawings.

FIG. 1 is a side view of an outboard motor according to the present invention, and FIG.
Is a side sectional view of the upper part of the outboard motor.

First, the overall configuration of the outboard motor 1 will be outlined with reference to FIG.

An outboard motor 1 shown in FIG. 1 is attached to a stern plate of a hull (not shown) by a clamp bracket 2, and a swivel bracket 3 for elastically supporting an outboard motor main body 1a is mounted on the clamp bracket 2 with a tilt shaft. 4 pivotally attachable to the upper and lower sides.

The outboard motor main body 1a has a housing composed of a cowling 5, an upper case 6, and a lower case 7, and the cowling 5 is composed of an upper cowl 5a and a bottom cowl 5b, which are upper and lower two stages. A four-cycle engine 8 as a drive source is housed inside. A crankshaft 9 disposed above and below the four-cycle engine 8 has an upper case 6 and a lower case 7.
A drive shaft 10 installed vertically therein is connected, and a lower end of the drive shaft 10 is connected to a propeller shaft 12 via a forward / reverse switching mechanism 11.

The propeller shaft 12 is connected to the drive shaft 10
Are arranged at right angles to the front-back direction (left-right direction in FIG. 1),
A propeller 13 is provided at the rear end extending outside the lower case 7.
Is bound.

The four-cycle engine 8 is a water-cooled four-cylinder engine in which four cylinders are arranged in a vertical direction (up-down direction), and the crankshaft 9 common to each cylinder is arranged in a vertical direction. It is arranged in. An oil pan 41 is built in a lower portion of the engine 8.
Note that, as shown in detail in FIG.
Reference numeral 4 denotes a crankcase, 15 denotes a cylinder body, 16 denotes a cylinder head, and 17 denotes a cylinder head cover. A total of four pistons (not shown) are vertically slidably fitted in the cylinder body 15. Each piston is connected to the crankshaft 9 via a connecting rod (not shown).

Thus, as shown in FIG.
A molding air duct 18 is attached to a rear portion of the upper surface of the cowling 5, and an intake port 18 a is opened rearward in the molding air duct 18. Is stored. Note that two intake ducts 19 are provided in the left-right direction (the direction perpendicular to the paper surface of FIG. 2), and the upper surface thereof is open. One of the intake ducts 19 is connected to the intake chuck bar of the engine 8, and the other is open into the cowling 5.

A part of the upper surface of the cowling 5 is opened and closed by a duct 20 connected to the molding air duct 18.
The openable / closable duct 20 is supported so as to be able to open and close with respect to the cowling 5 by pivotally supporting an intermediate portion of a lever 21 attached thereto to the cowling 5 by a shaft 22.

The openable / closable duct 20 is opened and closed by a solenoid 23 installed in the cowling 5 (upper cowl 5a). The solenoid 23 is supported by a stay 24 projecting from the cowling 5. The tip of the rod 23a is the lever 2 of the openable / closable duct 20.
1 end. The solenoid 23 is electrically connected to a controller 26 and a battery (not shown) via a lead wire 25 routed along the inner wall of the cowling 5. The solenoid 23 is a cowling 5
The controller 26 and the battery are installed on the bottom cowl 5b side while the controller 26 and the battery are installed on the side of the upper cowl 5a.
A and 27B are interposed, and the upper cowl 5a is assembled to the bottom cowl 5b to form the coupler 27.
A and 27B are connected so that the solenoid 23 is electrically connected to the controller 26 and the battery via the lead wire 25.

During the operation of the four-cycle engine 8, the controller 26 does not energize the solenoid 23, and the openable / closable duct 20 is closed as shown by the solid line in FIG.

Then, when the four-cycle engine 8 is stopped, the controller 26 energizes the solenoid 23 from the battery (not shown) via the lead wire 25 for a fixed time. Then, since the rod 23a of the solenoid 23 is extended to rotate the lever 21 of the openable duct 20 about the shaft 22, the openable duct 20 is opened as shown by a chain line in FIG.

Therefore, the hot air in the cowling 5 is discharged to the outside of the cowling 5 through the openable / closable duct 20 until a predetermined time elapses after the four-cycle engine 8 is stopped. Cowling 5
The rise in temperature inside is suppressed to prevent the generation of air bubbles and vapor in the fuel supply line, the starting failure of the four-cycle engine 8 is eliminated, and the adverse thermal effects on auxiliary equipment and electrical components are also eliminated. You.

The ambient temperature inside the cowling 5 is detected, and while this temperature exceeds a set value, the solenoid 23
, The opening / closing duct 20 may be opened.
Alternatively, the openable / closable duct 20 may be manually opened when the engine 8 is stopped. [Second Invention] Next, an embodiment of the second invention will be described with reference to the accompanying drawings.

<Embodiment 1> FIG. 3 is a side sectional view of an upper part of an outboard motor according to Embodiment 1 of the second invention, and FIGS. 4 and 5 are electric circuit diagrams for controlling driving of an exhaust fan. In FIG. 3, the same elements as those shown in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted.

In the present embodiment, the space defined by the molding air duct 18 attached to the upper surface of the cowling 5 and the cowling 5 is divided into the chambers S1 and S2 by the partition wall 28 projecting from the cowling 5. An opening 18a formed in the molding air duct 18 is open in one chamber S1, and an oblong exhaust port 18b formed in a side of the molding air duct 18 is open in the other chamber S2. ing.

In the chamber S2, an exhaust duct 29, which is integrally provided on the upper surface of the cowling 5, is opened. In the exhaust duct 29, a cylindrical housing 30 is provided with a screw 31.
Installed by. And the housing 30
Inside, an electric motor 3 operated by a battery (not shown)
2 and an exhaust fan 33 that is driven to rotate by the electric motor 32. The electric motor 32 is electrically connected to a controller 26 and a battery (not shown) via a lead wire 25 routed along the inner wall of the cowling 5.

During operation of the four-cycle engine 8, the controller 26 does not energize the electric motor 32, and the exhaust fan 33 is not driven to rotate by the electric motor 32.

Then, when the four-cycle engine 8 is stopped, the controller 26 energizes the electric motor 32 from the battery (not shown) via the lead wire 25 for a fixed time. Then, the electric motor 32 operates to drive the exhaust fan 33 to rotate, and the hot air in the cowling 5 is exhausted from the exhaust port 18 b to the outside of the cowling 5 by the exhaust fan 33. Of the fuel supply line to prevent the generation of air bubbles and vapor, the starting failure of the four-cycle engine 8 is eliminated, and the adverse thermal effects on the auxiliary equipment and electric components are also eliminated. .

In the present embodiment, the intake port 18
a and the exhaust port 18b are separated by the partition wall 28, so that the hot air in the cowling 5 discharged from the exhaust port 18b during the operation of the engine 8 is not drawn into the engine 8 from the intake port 18a. High filling efficiency is ensured and its performance is prevented from being reduced.

Here, another method of controlling the drive of the exhaust fan 33 will be described with reference to FIGS. 4 and 5, respectively.

That is, in the method shown in FIG.
A power supply line for supplying electric power to the electric motor 32 of the exhaust fan 33 is provided by bypassing a main switch (or main relay) 35 provided in a power supply line from the engine to the engine 8, and a temperature detection switch 36 is provided in the middle of the power supply line. Is provided. The temperature detection switch 36 is a mechanical switch using a bimetal, wax, or the like, and detects the temperature of the engine 8, the ambient temperature in the cowling 5, the temperature of the lubricating oil, and the like. When turned on, the electric motor 32 and the battery 34 are electrically connected.

Thus, according to this method, regardless of the ON / OFF of the main switch 35 (that is, the operation / stop of the engine 8), when the detected temperature exceeds the set value, the temperature detection switch 36 is activated. When the electric motor 32 is turned on and the electric motor 32 is energized, the exhaust fan 33 is driven to rotate, so that the hot air in the cowling 5 is discharged to the outside of the cowling 5 and the temperature rise in the cowling 5 is suppressed.

In the method shown in FIG. 5, when the main switch 35 is turned off and the engine 8 is stopped,
N, a timer switch 37 which is turned off when a predetermined time has elapsed is provided. According to this method, the timer switch 37 is turned off until the predetermined time elapses after the engine 8 stops, as in the above-described embodiment. Since the exhaust fan 33 is driven to rotate and the hot air inside the cowling 5 is exhausted outside the cowling 5, the temperature rise inside the cowling 5 is suppressed even after the engine 8 is stopped, and various problems associated with abnormal temperature rise are solved. Is done.

Second Embodiment Next, a second embodiment of the second invention will be described with reference to FIGS. FIG. 6 is a side sectional view of the upper part of the outboard motor according to Embodiment 2 of the second invention,
7 and 8 are plan sectional views schematically showing the positional relationship between the lower end opening of the intake duct and the exhaust port. In FIG. 6, the same elements as those shown in FIGS. 2 and 3 are denoted by the same reference numerals. In the following, description thereof will be omitted.

In the present embodiment, an intake duct 38 for introducing outside air into the cowling 5 from an intake port 18a opened on the rear upper surface of the cowling 5 is provided along the inner surface of the rear wall of the cowling 5. An intake fan 40 rotatably driven by an electric motor 39 is provided in an upper opening 38a of the intake duct 38, and a lower end of the intake duct 38 is opened as an opening 38b in a rear bottom surface in the cowling 5.

An exhaust port 18b is formed at the front upper surface of the cowling 5, and the lower end opening 38b of the intake duct 38 into the cowling 5 and the exhaust port 18b are viewed from the side as shown in FIG. It is arranged on the diagonal of the cowling 5. Note that the lower end opening 38b and the exhaust port 18b of the intake duct 38 are arranged on the center line as shown in FIG. 7 in plan view, or are arranged diagonally as shown in FIG.

In this embodiment, for example, if the intake fan 40 is driven to rotate by the battery power for a predetermined time after the four-cycle engine 8 is stopped, the outside air is taken in by the intake fan 40. Mouth 18
a is drawn into the intake duct 38, and this outside air crosses the engine 8 from the lower end opening 38b of the intake duct 38 toward the exhaust port 18b as shown by an arrow in FIG. And the engine 8 is effectively cooled in the process. Then, the hot air in the cowling 5 whose temperature has been increased by cooling the engine 8 is discharged out of the cowling 5 from the exhaust port 18b.

Therefore, also in the present embodiment, the temperature rise in the cowling 5 after the engine 8 is stopped is suppressed, and the generation of bubbles and vapor in the fuel supply line is prevented, and the starting failure of the four-cycle engine 8 is poor. Is eliminated, and the adverse thermal effect on the auxiliary equipment, electrical components, and the like is also eliminated.

It is needless to say that the above-described embodiments of the first invention and the embodiments of the second invention may be arbitrarily combined and implemented.

[0047]

As is apparent from the above description, claim 1
According to the invention described in (2), if the openable duct is opened at least when the engine is stopped, hot air in the cowling is discharged to the outside of the cowling through the openable duct, so that the temperature inside the cowling increases even after the engine is stopped. As a result, the generation of bubbles and vapor in the fuel supply line is prevented, so that the starting failure of the engine is eliminated, and the adverse effects of heat on accessories, electric components and the like are also eliminated.

According to the third or fourth aspect of the present invention, at least when the engine is stopped, if the fan is driven by the electric motor operated by the battery power supply, the hot air in the cowling is discharged from the exhaust port to the outside of the cowling by the fan. Therefore, even after the engine is stopped, the rise in temperature inside the cowling is suppressed, preventing the generation of air bubbles and vapor in the fuel supply line, eliminating poor engine startup and eliminating heat to auxiliary equipment and electrical components. This has the effect of also eliminating the adverse effects of environmental impact.

According to the fifth aspect of the present invention, since the intake port and the exhaust port opened to the cowling are separated by the partition wall, the hot air in the cowling discharged from the exhaust port during operation of the engine is discharged from the intake port to the engine. Thus, there is obtained an effect that a high filling efficiency is secured in the engine and a decrease in performance thereof is prevented.

According to the sixth aspect of the present invention, the opening of the intake duct for introducing outside air into the cowling into the cowling and the exhaust port are arranged on the diagonal of the cowling in a side view. A fan driven after the engine stops generates a flow of outside air in the cowling along a diagonal line in a side view, and the flow of the outside air effectively cools the engine, and the hot air in the cowling is discharged from the exhaust port to the outside of the cowling. The effect is obtained.

[Brief description of the drawings]

FIG. 1 is a side view of an outboard motor according to the present invention.

FIG. 2 is a side sectional view of an upper part of the outboard motor according to the first invention.

FIG. 3 is a side sectional view of an upper portion of the outboard motor according to the first embodiment of the second invention.

FIG. 4 is an electric circuit diagram showing another method of controlling the driving of an exhaust fan provided in the outboard motor according to Embodiment 1 of the second invention.

FIG. 5 is an electric circuit diagram showing another method for controlling the driving of the exhaust fan provided in the outboard motor according to Embodiment 1 of the second invention.

FIG. 6 is a side sectional view of an upper portion of an outboard motor according to Embodiment 2 of the second invention.

FIG. 7 is a plan sectional view schematically showing a positional relationship between an opening at the lower end of an intake duct and an exhaust port in an outboard motor according to Embodiment 2 of the second invention.

FIG. 8 is a plan sectional view schematically showing a positional relationship between an opening at a lower end of an intake duct and an exhaust port in an outboard motor according to Embodiment 2 of the second invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outboard motor 5 Cowling 8 4 cycle engine 18a Intake port 18b Exhaust port 20 Openable duct 23 Solenoid (actuator) 26 Controller (control means) 28 Partition wall 32,39 Electric motor 33 Exhaust fan (Fan) 34 Battery 36 Temperature detection switch (Control means) 37 Timer switch (Control means) 38 Intake duct 38b Lower end opening of intake duct 40 Intake fan (fan)

Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16M 1/00 B63H 21/26 Z

Claims (6)

[Claims] 1. An outboard motor comprising a four-stroke engine with a built-in oil pan and housed in a cowling, wherein the outboard motor comprises a part of the cowling which is opened or closed manually or automatically. Machine. 2. An actuator which is operated by a battery power supply to open and close the openable duct, and controls the operation of the actuator until a predetermined time elapses after the engine stops or the temperature in the cowling exceeds a set value. 2. The outboard motor according to claim 1, further comprising control means for opening the openable duct during the operation. 3. An outboard motor comprising a four-stroke engine with a built-in oil pan in a cowling, wherein a fan driven by an electric motor operated by a battery power source is provided in the cowling, and hot air in the cowling is removed from the cowling. An outboard motor comprising: a cowling having an exhaust port for discharging air to the cowling; and control means for controlling the operation of the electric motor. 4. The control means controls the operation of the electric motor so as to drive the fan until a predetermined time elapses after the engine is stopped or while the temperature inside the cowling exceeds a set value. The outboard motor according to claim 3, characterized in that: 5. The outboard motor according to claim 3, wherein an intake port for introducing outside air into the cowling and the exhaust port are separated by a partition. 6. The cowling according to claim 3, wherein an opening portion of the intake duct for introducing outside air into the cowling into the cowling and the exhaust port are arranged on a diagonal line of the cowling in a side view. 5. The outboard motor according to 5.